Numbers 35:11-15

111then you shall select for yourselves cities to be your 2cities of refuge, so that the one who commits manslaughter by 3killing a person 4unintentionally may flee there. 125The cities shall 6serve you as a refuge from the avenger, so that the one who commits manslaughter does not die until he stands before the congregation for 7trial. 13So the cities which you are to provide shall be six cities of refuge for you. 14You 8shall provide three cities across the Jordan, and three cities 9in the land of Canaan; they are to be cities of refuge. 15These six cities shall be a refuge for the sons of Israel, for the stranger, and for the foreign resident among them; so that anyone who 10kills a person 11unintentionally may flee there.